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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /io_uring/filetable.c
parentInitial commit. (diff)
downloadlinux-upstream/6.6.15.tar.xz
linux-upstream/6.6.15.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'io_uring/filetable.c')
-rw-r--r--io_uring/filetable.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/io_uring/filetable.c b/io_uring/filetable.c
new file mode 100644
index 0000000000..e7d749991d
--- /dev/null
+++ b/io_uring/filetable.c
@@ -0,0 +1,178 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/nospec.h>
+#include <linux/io_uring.h>
+
+#include <uapi/linux/io_uring.h>
+
+#include "io_uring.h"
+#include "rsrc.h"
+#include "filetable.h"
+
+static int io_file_bitmap_get(struct io_ring_ctx *ctx)
+{
+ struct io_file_table *table = &ctx->file_table;
+ unsigned long nr = ctx->file_alloc_end;
+ int ret;
+
+ if (!table->bitmap)
+ return -ENFILE;
+
+ do {
+ ret = find_next_zero_bit(table->bitmap, nr, table->alloc_hint);
+ if (ret != nr)
+ return ret;
+
+ if (table->alloc_hint == ctx->file_alloc_start)
+ break;
+ nr = table->alloc_hint;
+ table->alloc_hint = ctx->file_alloc_start;
+ } while (1);
+
+ return -ENFILE;
+}
+
+bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
+{
+ table->files = kvcalloc(nr_files, sizeof(table->files[0]),
+ GFP_KERNEL_ACCOUNT);
+ if (unlikely(!table->files))
+ return false;
+
+ table->bitmap = bitmap_zalloc(nr_files, GFP_KERNEL_ACCOUNT);
+ if (unlikely(!table->bitmap)) {
+ kvfree(table->files);
+ return false;
+ }
+
+ return true;
+}
+
+void io_free_file_tables(struct io_file_table *table)
+{
+ kvfree(table->files);
+ bitmap_free(table->bitmap);
+ table->files = NULL;
+ table->bitmap = NULL;
+}
+
+static int io_install_fixed_file(struct io_ring_ctx *ctx, struct file *file,
+ u32 slot_index)
+ __must_hold(&req->ctx->uring_lock)
+{
+ struct io_fixed_file *file_slot;
+ int ret;
+
+ if (io_is_uring_fops(file))
+ return -EBADF;
+ if (!ctx->file_data)
+ return -ENXIO;
+ if (slot_index >= ctx->nr_user_files)
+ return -EINVAL;
+
+ slot_index = array_index_nospec(slot_index, ctx->nr_user_files);
+ file_slot = io_fixed_file_slot(&ctx->file_table, slot_index);
+
+ if (file_slot->file_ptr) {
+ ret = io_queue_rsrc_removal(ctx->file_data, slot_index,
+ io_slot_file(file_slot));
+ if (ret)
+ return ret;
+
+ file_slot->file_ptr = 0;
+ io_file_bitmap_clear(&ctx->file_table, slot_index);
+ }
+
+ ret = io_scm_file_account(ctx, file);
+ if (!ret) {
+ *io_get_tag_slot(ctx->file_data, slot_index) = 0;
+ io_fixed_file_set(file_slot, file);
+ io_file_bitmap_set(&ctx->file_table, slot_index);
+ }
+ return ret;
+}
+
+int __io_fixed_fd_install(struct io_ring_ctx *ctx, struct file *file,
+ unsigned int file_slot)
+{
+ bool alloc_slot = file_slot == IORING_FILE_INDEX_ALLOC;
+ int ret;
+
+ if (alloc_slot) {
+ ret = io_file_bitmap_get(ctx);
+ if (unlikely(ret < 0))
+ return ret;
+ file_slot = ret;
+ } else {
+ file_slot--;
+ }
+
+ ret = io_install_fixed_file(ctx, file, file_slot);
+ if (!ret && alloc_slot)
+ ret = file_slot;
+ return ret;
+}
+/*
+ * Note when io_fixed_fd_install() returns error value, it will ensure
+ * fput() is called correspondingly.
+ */
+int io_fixed_fd_install(struct io_kiocb *req, unsigned int issue_flags,
+ struct file *file, unsigned int file_slot)
+{
+ struct io_ring_ctx *ctx = req->ctx;
+ int ret;
+
+ io_ring_submit_lock(ctx, issue_flags);
+ ret = __io_fixed_fd_install(ctx, file, file_slot);
+ io_ring_submit_unlock(ctx, issue_flags);
+
+ if (unlikely(ret < 0))
+ fput(file);
+ return ret;
+}
+
+int io_fixed_fd_remove(struct io_ring_ctx *ctx, unsigned int offset)
+{
+ struct io_fixed_file *file_slot;
+ int ret;
+
+ if (unlikely(!ctx->file_data))
+ return -ENXIO;
+ if (offset >= ctx->nr_user_files)
+ return -EINVAL;
+
+ offset = array_index_nospec(offset, ctx->nr_user_files);
+ file_slot = io_fixed_file_slot(&ctx->file_table, offset);
+ if (!file_slot->file_ptr)
+ return -EBADF;
+
+ ret = io_queue_rsrc_removal(ctx->file_data, offset,
+ io_slot_file(file_slot));
+ if (ret)
+ return ret;
+
+ file_slot->file_ptr = 0;
+ io_file_bitmap_clear(&ctx->file_table, offset);
+ return 0;
+}
+
+int io_register_file_alloc_range(struct io_ring_ctx *ctx,
+ struct io_uring_file_index_range __user *arg)
+{
+ struct io_uring_file_index_range range;
+ u32 end;
+
+ if (copy_from_user(&range, arg, sizeof(range)))
+ return -EFAULT;
+ if (check_add_overflow(range.off, range.len, &end))
+ return -EOVERFLOW;
+ if (range.resv || end > ctx->nr_user_files)
+ return -EINVAL;
+
+ io_file_table_set_alloc_range(ctx, range.off, range.len);
+ return 0;
+}